The present invention relates to an improvement of blades of forced and induced draft fans for sucking and exhausting gases containing dust.
Easily worn are the blades of fans for sucking gases containing a large quantity of dust and discharging them as in the case of the gases discharged from coal-burned boilers. Wear at the leading edge of each blade extending about 3/4-1/4 in length thereof from the blade tip is especially pronounced and greatly influences a useful life of the blade. Therefore, there has been an increasing demand to take some countermeasures to minimize wear of the fan blades, thereby prolonging a useful life thereof.
In order to overcome the above described problem, there has been proposed and demonstrated a fan blade the leading edge of which is covered with a stainless-steel plate which in turn is plated with hard chrome.
With this construction of the fan blades, there arises the problem that hard chrome plating is limitative in thickness and prolongation of a useful life is extremely slight.
In view of the above, one of the objects of the present invention is to provide a fan blade a useful life of which is prolonged even when gases containing dust are handled.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of preferred embodiments thereof taken in conjunction with the accompanying drawings.